1. Field of the Invention
The present invention relates to a locking device designed to secure an electrical connection plug plugged into a measuring instrument.
2. Description of the Prior Art
In the field of electrical connection means, locking devices are known, which generally consist of an elastic part secured to the instrument and which cooperates, through its shape, with a part of the plug to retain the plug in position. This part can be elastically deformed in order to release the plug.
Measuring instruments generally comprise two cords terminating in plugs, on the instrument side, and probes, on the measuring point side. The plugs of these cords plug into two or several sockets provided in the housing of the instrument. These plugs are retained in place by the friction between the connecting components of the plug and the socket.
However, it happens that the plugs are submitted to relatively strong forces resulting from a pulling load on the cords and the connection components can thus be damaged, whereas the connection can unexpectedly be released.
The addition of locking means to secure the plugs in measuring instruments is therefore desirable. However, this should meet a number of conditions, the main one being that the instrument should entail slight modifications only and this, without any additional cost. In fact the locking device is not always necessary and a special version of the instrument comprising a locking device should be avoided. Obviously, sealing of the housing must be preserved. It is further necessary to preserve the aesthetic appearance of the instrument. Finally, of course, the locking device itself must be reliable and cheap.
It is an object of the present invention to provide a locking device which satisfies these conditions.